No way, that can't be true... (Sad)

I'll tell you briefly what happened. I bought 'Dragon Quest Monsters 2: Iru and Luca's Marvelous Mysterious Journey' which became more affordable due to a slight price drop during the summer sale. As soon as I started the game, excited about the new adventures and battles that awaited, I received this notice (see image). I loved the battles more than anything... I felt great joy in being able to fight various opponents with my trained monsters. Maybe I wanted to escape the hardships of reality by immersing myself in battles. That's why this notice hit me so hard... It was really tough... The days of fierce battles against other players have ended. What should I seek in this game now... Tell me... The Emblem of Roto offers no answers...